ARID1A and neoplasm: This implicates these genes as tumor suppressors, in line with prior observations that BRG1-associated factor complexes can inhibit cell cycle progression by repressing the activity of several E2F-repsonsive promoters via their association with RB1.8, 69, 70 ARID1A can also directly bind p53, enhance its transactivation activity and promote the expression of the cell cycle inhibitor CDKN1A.71 Interestingly, ARID1A also regulates cellular functions associated with B-cell biology.